Make spacer attribute mapping code not depend on data in the style context (which attribute mapping code should not do). (Bug 449435) r+sr=bzbarsky

content/html/content/src/nsHTMLSharedElement.cpp

@@ -47,7 +47,6 @@
 #include "nsPresContext.h"
 #include "nsRuleData.h"
 #include "nsMappedAttributes.h"
-#include "nsStyleContext.h"
 
 // XXX nav4 has type= start= (same as OL/UL)
 extern nsAttrValue::EnumTable kListTypeTable[];
@@ -239,11 +238,23 @@ SpacerMapAttributesIntoRule(const nsMappedAttributes* aAttributes,
   nsGenericHTMLElement::MapImageMarginAttributeInto(aAttributes, aData);
   nsGenericHTMLElement::MapImageSizeAttributesInto(aAttributes, aData);
 
+  if (aData->mSIDs & (NS_STYLE_INHERIT_BIT(Position) |
+                      NS_STYLE_INHERIT_BIT(Display))) {
+    PRBool typeIsBlock = PR_FALSE;
+    const nsAttrValue* value = aAttributes->GetAttr(nsGkAtoms::type);
+    if (value && value->Type() == nsAttrValue::eString) {
+      const nsString& tmp(value->GetStringValue());
+      if (tmp.LowerCaseEqualsLiteral("line") ||
+          tmp.LowerCaseEqualsLiteral("vert") ||
+          tmp.LowerCaseEqualsLiteral("vertical") ||
+          tmp.LowerCaseEqualsLiteral("block")) {
+        // This is not strictly 100% compatible: if the spacer is given
+        // a width of zero then it is basically ignored.
+        typeIsBlock = PR_TRUE;
+      }
+    }
+
     if (aData->mSIDs & NS_STYLE_INHERIT_BIT(Position)) {
-    const nsStyleDisplay* display = aData->mStyleContext->GetStyleDisplay();
-
-    PRBool typeIsBlock = (display->mDisplay == NS_STYLE_DISPLAY_BLOCK);
-
       if (typeIsBlock) {
         // width: value
         if (aData->mPositionData->mWidth.GetUnit() == eCSSUnit_Null) {
@@ -281,6 +292,7 @@ SpacerMapAttributesIntoRule(const nsMappedAttributes* aAttributes,
         }
       }
     }
+
     if (aData->mSIDs & NS_STYLE_INHERIT_BIT(Display)) {
       const nsAttrValue* value = aAttributes->GetAttr(nsGkAtoms::align);
       if (value && value->Type() == nsAttrValue::eEnum) {
@@ -295,21 +307,15 @@ SpacerMapAttributesIntoRule(const nsMappedAttributes* aAttributes,
         }
       }
 
+      if (typeIsBlock) {
         if (aData->mDisplayData->mDisplay.GetUnit() == eCSSUnit_Null) {
-      const nsAttrValue* value = aAttributes->GetAttr(nsGkAtoms::type);
-      if (value && value->Type() == nsAttrValue::eString) {
-        nsAutoString tmp(value->GetStringValue());
-        if (tmp.LowerCaseEqualsLiteral("line") ||
-            tmp.LowerCaseEqualsLiteral("vert") ||
-            tmp.LowerCaseEqualsLiteral("vertical") ||
-            tmp.LowerCaseEqualsLiteral("block")) {
-          // This is not strictly 100% compatible: if the spacer is given
-          // a width of zero then it is basically ignored.
           aData->mDisplayData->mDisplay.SetIntValue(NS_STYLE_DISPLAY_BLOCK,
                                                     eCSSUnit_Enumerated);
         }
       }
     }
+    // Any new structs that don't need typeIsBlock should go outside
+    // the code that calculates it.
   }
 
   nsGenericHTMLElement::MapCommonAttributesInto(aAttributes, aData);